Lumbar Strain

Question 1

Definition/Description

Answer 1

Lumbar strain is a commonly wielded diagnosis (Depalma 2011, Houglum 2001) for mechanical low back pain but is without anatomical or histologic evidence.(Depalma 2011) Much of the knowledge of lumbar strain is extrapolated from peripheral muscle strains. (Depalma 2011)

In strains, the muscle is subjected to an excessive tensile force leading to the overstraining of the myofibres and, consequently, to their rupture near the myotendinous junction. (Jarvinen 2007, Depalma 2011)

The current classification of muscle injuries identifies mild, moderate and severe injuries based on the clinical impairment they bring about.

Question 2

Clinically Relevant Anatomy

Answer 2

The lumbar spine consists of 5 moveable vertebrae numbered L1-L5. The complex anatomy of the lumbar spine is a remarkable combination of these strong vertebrae, multiple bony elements linked by joint capsules, and flexible ligaments/tendons, large muscles, and highly sensitive nerves. It also has a complicated innervation and vascular supply.
The lumbar spine is designed to be incredibly strong, protecting the highly sensitive spinal cord and spinal nerve roots. At the same time, it is highly flexible, providing for mobility in many different planes including flexion, extension, side bending, and rotation. [level of evidence: [level of evidence: 2C]

Lumbar strain can origine in the following muscles (Houglum 2001, Putz 1997, Meeusen1 2001): M. erector spinae (M. iliocostales, M longissimus, M. spinalis) M semispinales, Mm multifidi, Mm rotatores M. quadratus lumborum M. serratus posterior

Question 3

Epidemiology /Etiology

Answer 3

Strains are defined as tears (partial or complete) of the muscle-tendon unit. Muscle strains and tears most frequently result from a violent muscular contraction during an excessively forceful muscular stretch. Any posterior spinal muscle and its associated tendon can be involved, although the most susceptible muscles are those that span several joints.You can define acute and chronic lumbar strain. Acute pain is most intense 24 to 48 hours after injury. Chronic strains are characterized by continued pain attributable to muscle injury. level of evidence: 2C]

Low back pain is the second most common symptom that causes patients to seek medical attention in the outpatient setting. Approximately 70% of adults have an episode of LBP as a result of work or play

Question 4

Differential Diagnosis

Answer 4

Degenerative disk or facet process (Leven of Evidence:
- localized lumbar pain

   - diffuse pain in lumber muscles

Herniated disk
Osteoporotic compression fracture (Level of Evidence: 2C)
- spine tenderness
Spinal stenosis or osteoarthritis
- may have weak/asymmetric reflexes

   - decreased in extension

Spondylolisthesis (level of evidence 5)

   - exaggerating lumbar lordosis
   - palpable ‘step-off’

   - tight hamstings

Ankylosing spondylitis
- tenderness over sacro-iliacal joints
- decreased back motion
Diagnostic Procedur